DPYSL2 is a novel regulator for neural stem cell differentiation in rats: revealed by Panax notoginseng saponin administration

Liu-Lin Xiong,Ting-Hua Wang,Yue Hu,Guang-Hui Xiu,De-Lu Qiu,Ya Jiang,Qing-Jie Xia,You-Cui Wang,Li Chen,Mohammed Al-Hawwas

doi:10.1186/s13287-020-01652-4

Abstract

BackgroundThe limited neuronal differentiation of the endogenous or grafted neural stem cells (NSCs) after brain injury hampers the clinic usage of NSCs. Panax notoginseng saponins (PNS) were extensively used for their clinical value, such as in controlling blood pressure, blood glucose, and inhibiting neuronal apoptosis and enhancing neuronal protection, but whether or not it exerts an effect in promoting neuronal differentiation of the endogenous NSCs is completely unclear and the potential underlying mechanism requires further exploration.MethodsFirstly, we determined whether PNS could successfully induce NSCs to differentiate to neurons under the serum condition. Mass spectrometry and quantitative polymerase chain reaction (Q-PCR) were then performed to screen the differentially expressed proteins (genes) between the PNS + serum and serum control group, upon which dihydropyrimidinase-like 2 (DPYSL2), a possible candidate, was then selected for the subsequent research. To further investigate the actual role of DPYSL2 in the NSC differentiation, DPYSL2-expressing lentivirus was employed to obtain DPYSL2 overexpression in NSCs. DPYSL2-knockout rats were constructed to study its effects on hippocampal neural stem cells. Immunofluorescent staining was performed to identify the differentiation direction of NSCs after 7 days from DPYSL2 transfection, as well as those from DPYSL2-knockout rats.ResultsSeven differentially expressed protein spots were detected by PD Quest, and DPYSL2 was found as one of the key factors of NSC differentiation in a PNS-treated condition. The results of immunostaining further showed that mainly Tuj1 and GFAP-positive cells increased in the DPYSL2-overexpressed group, while both were depressed in the hippocampal NSCs in the DPYSL2-knockout rat.ConclusionsThe present study revealed that the differentiation direction of NSCs could be enhanced through PNS administration, and the DPYSL2 is a key regulator in promoting NSC differentiation. These results not only emphasized the effect of PNS but also indicated DPYSL2 could be a novel target to enhance the NSC differentiation in future clinical trials.

Highlights

Neural stem cells (NSCs) existing in the subventricle zone of the brain’s germinal region and the subgranular zone of the hippocampus are capable of self-renewing, proliferating, migrating, and differentiating into various types of cells within the brain and spinal cord tissue [13, 41]
Observation and identification of the cultured neural stem cells (NSCs) The cells isolated from the neonatal rats (1 p) turned out to be spheres consisting of several tens of cellular clumps on 2–3 days after isolation and showed the fluctuant growth state (Fig. 1a)
Panax notoginseng saponins (PNS) could induce NSCs to differentiate into neurons in the serum condition The P2 NSCs were cultured in the neural basal medium supplemented with PNS for 7 days

Summary

Introduction

Neural stem cells (NSCs) existing in the subventricle zone of the brain’s germinal region and the subgranular zone of the hippocampus are capable of self-renewing, proliferating, migrating, and differentiating into various types of cells within the brain and spinal cord tissue [13, 41]. NSC differentiation into neurons, astrocytes, and oligodendrocytes could replace necrotic cells resulting from injuries to promote the structural and functional repair of the brain and spinal cord [50]. This self-renewal is not adequate for the recovery of neurological function after brain injury [1, 32, 47]. The limited neuronal differentiation of the endogenous or grafted neural stem cells (NSCs) after brain injury hampers the clinic usage of NSCs. Panax notoginseng saponins (PNS) were extensively used for their clinical value, such as in controlling blood pressure, blood glucose, and inhibiting neuronal apoptosis and enhancing neuronal protection, but whether or not it exerts an effect in promoting neuronal differentiation of the endogenous NSCs is completely unclear and the potential underlying mechanism requires further exploration

Methods

Results

Conclusion